Electroluminescent (EL) apparatus may be classified as organic or inorganic. Electroluminescent apparatus exhibit high visibility due to inherent self-emission characteristics and provide excellent impact resistance and handling ability. As a result, research, development and practical utilization of EL apparatus as pixels for graphic display, pixels for a television image display and as a light source are currently underway.
Organic EL apparatus normally include a laminate structure having, among other things, a light-emitting layer formed of a fluorescent organic solid and electrode apparatus. This laminate structure is normally formed on a substrate such as glass. This type of organic EL apparatus exhibits light emission characteristics provided when electrons injected into the light-emitting layer are recombined. As a result, organic EL apparatus is actuated by a low voltage and exhibits a level of brightness proportional to the injected electric current. By changing the type of fluorescent organic solids comprising the light-emitting layer, light emission may be obtained through substantially the entire visible light region.
The fluorescent organic solids commonly used to form the light-emitting layer of organic EL apparatus are susceptible to water, oxygen and other environmental elements present in ambient conditions. Furthermore, electrode apparatus formed on the light-emitting layer is also prone to oxidation from exposure to water, oxygen, etc. As a result, conventional organic EL apparatus exhibit a short life as a usable device in atmospheric conditions. To increase the life of organic EL apparatus, electrode apparatus and the light emitting layer must be protected from water, oxygen and other environmental elements.
To increase the life of organic EL apparatus in this regard, various methods and techniques have been devised for encapsulating organic EL apparatus with protective layers of varying compositions. Although exemplary, such methods and techniques are difficult and expensive to implement, require specialized processing equipment or techniques, and/or yield largely nominal results.
Accordingly, it would be highly desirable to provide improved encapsulated organic EL apparatus and improved methods of encapsulating organic EL apparatus.
It is a purpose of the present invention to provide a new and improved method of encapsulating organic EL apparatus that is highly effective for extending operating life.
It is another purpose of the present invention to provide a new and improved method of encapsulating organic EL apparatus that is relatively easy to implement.
It is still another purpose of the present invention to provide a new and improved method of encapsulating organic EL apparatus that is relatively inexpensive.
It is a further purpose of the present invention to provide new and improved encapsulation for organic EL apparatus which prevents exposure to ambient environmental conditions.